Atomizers

ABSTRACT

A liquid atomizer comprises a first cylinder containing a hollow, first piston, an atomizing nozzle communicating with the hollow piston a second cylinder of smaller cross-section than the first and communicating therewith. A second piston is slidable in the second cylinder and valve means connected to the second piston serve to block communication between the hollow piston and the nozzle. First and second springs are provided which respectively bias the valve means to close off the communication with the nozzle and lie between the two cylinders to bias them apart.

1451 July 17,1973

1 1 ATOMIZERS Inventor: Michel Boris, Paris. France Primary Examiner-M.Henson Wood, Jr Assistant ExaminerMichael Mar Atl0rneyArnold RobinsonAssignee: Societe Technique de Pulverisation,

Paris, France [22] Filed: Apr. 10, 1972 [57] ABSTRACT A liquid atomizercomprises a first cylinder containing Appl. No.: 242,518

Foreign Application Priority Data a hollow, first piston, an atomizingnozzle communicating with the hollow piston a second cylinder of smallercross-section than the first and communicating therewith. A secondpiston is slidable in the second cylinder 1 Int Cl and valve meansconnected to the second piston serve to block communication between thehollow piston and Field of Search....................

the nozzle. First and second springs are provided WlllCh respectivelybias the valve means to close off the communication with the nozzle andlie between the two cylinders to bias them apart.

References Cited UNITED STATES PATENTS 3,359,917 Cooprider......,.3,362,344 Duda........... 3,463,093 Pfeiffer et Patented July 17, 1973 2Sheets-Sheet 1 1 mm Bwjww A n P/ 4/2 gvvwv mun I a g Patented July 17,1973 2 Sheets-Sh. a

ATOMIZERS BACKGROUND OF THE INVENTION 1. Field of the Invention.

This invention relates to liquid atomizers, particularly of perfume.

2. Description of the Prior Art.

A liquid atomizer has been proposed comprising a first cylinder in whicha hollow piston is slidably mounted connected to an atomization tube, asecond cylinder of smaller section than the first, which communicateswith the first cylinder and in which is slidably mounted a pistonconnected to a valve suitable for interrupting communication between thefirst cylinder and the atomization tube, and resilient means acting onthe second piston and biasing the valve into the position in which thesaid communication is interrupted, the assembly of the two cylindersdefining a space which communicates with a plunger tube through anon-return valve.

In this prior proposal, when the first piston is moved, it carries withit the second piston through the intermediary of the valve, but theavailable space for liquid decreases, since the second piston has asection which is smaller than that of the first. The pressure of theliquid in the two cylinders increases so that the second piston tends tomove with respect to the first against the action of resilient meanswhich act on it. When this pressure reaches a sufficient value tobalance this action, the second piston moves whilst carrying with it thevalve connected with it so that the cylinders are put in communicationwith the atomization tube. The liquid contained in the cylinders is thusonly atomized when its pressure reaches a predetermined value, whichavoids the production of non-atomized drops, which phenomena would occurif the cylinders were placed in communication with the tube from thestart of the movement of the first piston. Similarly on the terminationof the movement of the first piston, the valve interruptingcommunication between the cylinders and the,

tube when the liquid pressure exerts on the second piston a force lowerthan the return force of the resilient means.

The atomizers of the type hereinbefore outlined, have thedisadvantage ofdifiicult priming since the delivery pressure increases progressively asthe hollow piston is plunged downwardly. Moreover, the atomizer mustinclude a valve preventing return to the liquid reservoir which isprovided in the first cylinder; this inlet valve is generally carried bythe small piston and is thus movable with respect to the casing of thepump. It has been established that when the delivery valve leaves itsblocking position, the inlet valve has a tendency to leave its seat,which causes return to the reservoir of a certain amount of liquidcontained in the first cylinder; the loss of pressure which follows thisspoils atomization.

The object of the present invention in an improvement in atomizers ofthe hereinbefore described type, which enables ready priming of theatomizer.

SUMMARY OF THE INVENTION According to the present invention, there isprovided in a liquid atomizer, a first cylinder, a hollow, first, pistonslidable in the first cylinder, an atomizing nozzle communicating withthe hollow piston, a second cylinder of smaller cross-section than thefirst cylinder and communicating with the first cylinder, a secondpiston slidable in the second cylinder, valve means connected to thesecond piston and disposed to interrupt communication between the firstcylinder and the nozzle, a first Spring acting on the second piston andbiasing the valve means to a position in which the said communication isinterrupted, a non-return valve, a plunger tube communicating with aspace defined by the two cylinders through the non-return valve, thesecond cylinder being disposed within the first piston and being movablewith respect to the first cylinder, and a second spring acting to biasthe two cylinders apart.

This construction overcomes at least partially the difficulties ofpreviously proposed atomizers, the spring interposed between the twocylinders ensuring release of fluid with a pressure of a constantpredetermined value. Furthermore, the advantage arises of increasing thevolume ejected by a given stroke of the larger piston.

In one preferred embodiment of the invention in which the atomizationtube is connected by an axial tube to the first piston, this axial tubecomprises a part of reduced internal diameter which defines a seat andthe second piston is connected to a rod which is slidably mounted in thetube and of which the end forms the delivery valve.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal,part-sectional view of an atomizer in accordance with the invention;

FIG. 2 is a longitudinal section, to an enlarged scale, of a part of theatomizer of FIG. 1;

FIG. 3 is a section on the line III-III of FIG. 2; and

FIG. 4 is a view in section of a part of the atomizer of FIG. 1 at theend of the stroke'of a push-button thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT As is illustrated in thedrawings, the atomizer in accordance with the invention comprises acylinder 1 which has in a lower part thereof a flange la and is securedto an internally-tapped bush 2 intended to closeoff a receivercontaining the liquid to be atomized. This cylinder 1 communicates, atits lower part, with a plunger tube 3 through a non-return valve 4.

In the cylinder 1 there is slidably mounted a hollow piston 5 secured toone of the ends of a tube 6; the other end of this tube is secured to apush-button 7 which comprises an atomization tube or nozzle 8 incommunication with the said tube 6. The portion of the piston 5 slidablymounted in the cylinder 1 is frustoconical and is connected through ashoulder 5a to the portion of the said piston which is fixed to the tube6. This latter portion is cylindrical and is itself slidably mountedwith a predetermined clearance, in a casing 9 fitted in the cylinderagainst the edge of which the shoulder 5a can just come into abutment.In the hollow piston 5 a blind bushing 10 is slidably mounted which isclosed at its end directed towards the non-return valve 4. A spring I Iis interposed between this bushing and the bottom of the cylinder 1; itbiases the bushing 10 against the end of the tube 6 and also the piston5 against the cover 9. Lateral passages 12 are formed in the internalface of the hollow piston 5 or, as shown, in the external face of thebushing 10 and openings 10 a formed in the internal end of this bushing,put the cylinder 1 in communication with the interior of the bushing 10.The latter forms a cylinder of smaller cross-section than the cylinder1, in which is slidably mounted a piston 13 dividing the interior of thecylinder into two chambers 14 and 15.

The piston 15 is rigid with a rod 16 which is disposed in the tube 6 andof which the end 16a forms a valve capable of being applied against aseat 60 formed in the tube 6 and constituting a restriction of thistube, so as to interrupt communication between the chamber 14 of thecylinder 10 and the nozzle 8. A spring 17 interposed between the bottomof the cylinder 10 and the piston 13 biases the valve 16a to seat on itsseat 6a.

A hole 18 is formed in the cylinder 1, substantially at the height ofthe upper edge of the cover 9; this hole opens into the interior of thebushing 2, and thus to the interior of the receptacle containing theliquid to be atomized. The lateral wall of the cylinder 10 has a hole 19opening into the chamber 15. This hole 19 lies opposite a hole 20 of thepiston 5 and thus puts the chamber 15 in communication with thereceptacle through the hole 18. Finally, the wall of the cylinder 1comprises an annular recess 1a upstream of the position occupied by theend of the piston 5, at the end of the stroke of the latter. When theatomizer is inoperative, the various parts occupy the position shown inFIG. 1. It is totally fluid-tight since the valve 16a is biased againstits seat by the spring 17 and the shoulder 5a is biased against the endof the cover by the spring 11.

The atomizer operates in the following manner. lnitially, thecylinder land the chamber 14 contain air. The user presses on the push-button 7 asindicated by the arrow f. This push-button drives the piston whichcompresses the air in the cylinder 1. At the end of its stroke, thepiston arrives opposite the recess la (FIG. 4) so that the aircompressed in thecylinder can escape to the exterior through theclearance space 21 existing between the internal wall of the cylinderand the piston, because of the frusto-conical form of the latter. Then,when the user releases the push-button, the piston 5 returns and againabuts against the internal wall of the cylinder 1, in such a manner thata depression is generated in the cylinder and causes the liquid to risethrough the plunger tube 3. At the end of two or three operations, thecylinder 1 and the chamber 14 are full of liquid to be atomized.

During the operation of the push-button 7, the piston 5 compresses theliquid contained in the cylinder 1 as well as that in the chamber 14.When the pressure attains a predetermined value, balancing the action ofthe spring 17, the piston 13 moves within the cylinder 10 whilstcarrying with it the rod 16. The valve 160 moves away from its seat 6aso that the pre-compressed liquid passes through the nozzle 8 whicheffects its atomization.

The displacement of the piston 5 follows, the liquid contained in thechamber I is returned to the nozzle 8 through bores 12, the chamber 14and the tube 6.

On completion of the movement, when the piston 5 arrives opposite therecess la, the pressure in the chamber 14 falls rapidly, in such amanner that the spring returns the valve 16a to its closed position; theliquid which can pass through the clearance 21 returns to the reservoirthrough the orifice 18. Then, when the user releases the push-button 7,the spring 11 returns the piston 5 and the members which are connectedto it to their initial positions, that it to say the cylinder 10,

the piston 13, the tube 6 and the rod 16. The assembly has then taken upagain the position of F IG. 1 and a depression of pressure is thusgenerated in the cylinder 1. As the valve 16a is held against its seat,liquid is aspirated into this chamber through the plunger tube 3 and thenon-return valve 4.

It will be apparent from the description which is given hereinbeforethat the liquid is atomized under a minimal pressure, depending on theforce of the spring 17 and that the atomization ceases when the pressurebecomes lower than the minimal pressure. The atomization is thuseffected always under good conditions so that liquid drops cannot form.

When the piston 5 is being displaced, the internal part of thereceptacle is put in communication with the atmosphere through theorifice l8 and the clearance between the casing 9 and the piston 5. Theair can thus enter the receptacle in order to compensate for the volumeof liquid which is transferred from this receptacle into the cylinder 1when the piston S rises again.

In the case where the liquid gains access to the cham-' ber 15 via therims of the piston 13 and the wall of the cylinder 10, this liquidreturns into the receptacle through the holes 19 and 20.

It will be clear that the present invention should not be considered tobe limited to the embodiment described and shown but covers, on thecontrary, all modifications within the scope of the appended claims.Thus, in particular, the piston S and the tube 6 may be formed of asingle part only.

I claim:

1. In a liquid atomizer,

a first cylinder,

a hollow, first, piston slidable in the first cylinder,

an atomizing nozzle communicating with the hollow piston,

a second cylinder of smaller cross-section than the first cylinder andcommunicating with the first cylinder,

a second piston slidable in the second cylinder,

valve means connected to the second piston and disposed to interruptcommunication between the first cylinder and the nozzle,

a first spring acting on the second piston and biasing the valve meansto a position in which the said communication is interrupted,

a non-return valve,

a plunger tube communicating with a space defined by the two cylindersthrough the non-return valve,

the second cylinder being disposed within the first piston and beingmovable with respect to the first cylinder, and

a second spring acting to bias the two cylinders apart.

2. An atomizer according to claim 1, further comprising a receptaclecontaining the liquid to be atomized, said first cylinder having anorifice communicating with the receptacle.

3. An atomizer according to claim 1 wherein the hollow, first, piston isexternally of frusto-conical form, at least over an end portion directedtowards the bottom of the first cylinder.

4. An atomizer according to claim 1, wherein the wall of the secondcyiinder has at least one opening providing communication between theinterior of the second cylinder and the interior of the first cylinder.

5. An atomizer according to claim 1, wherein the internal face of thefirst piston has at least one opening second piston slidably mounted onsaid tube and the end of which co-operates with said seat.

7. An atomizer according to claim 2, wherein the second cylinder hasopposite the second piston a discharge orifice aligned with an orificeformed in the first piston and communicating with the receptaclecontaining the liquid to be atomized.

1. In a liquid atomizer, a first cylinder, a hollow, first, pistonslidable in the first cylinder, an atomizing nozzle communicating withthe hollow piston, a second cylinder of smaller cross-section than thefirst cylinder and communicating with the first cylinder, a secondpiston slidable in the second cylinder, valve means connected to thesecond piston and disposed to interrupt communication between the firstcylinder and the nozzle, a first spring acting on the second piston andbiasing the valve means to a position in which the said communication isinterrupted, a non-return valve, a plunger tube communicating with aspace defined by the two cylinders through the non-return valve, thesecond cylinder being disposed within the first piston and being movablewith respect to the first cylinder, and a second spring acting to biasthe two cylinders apart.
 2. An atomizer according to claim 1, furthercomprising a receptacle containing the liquid to be atomized, said firstcylinder having an orifice communicating with the receptacle.
 3. Anatomizer according to claim 1 wherein the hollow, first, piston isexternally of frusto-conical form, at least over an end portion directedtowards the bottom of the first cylinder.
 4. An atomizer according toclaim 1, wherein the wall of the second cylinder has at least oneopening providing communication between the interior of the secondcylinder and the interior of the first cylinder.
 5. An atomizeraccording to claim 1, wherein the internal face of the first piston hasat least one opening providing communication between the interior of thesecond cylinder and the interior of the first cylinder.
 6. An atomizeraccording to claim 1, comprising a tube affording communication betweenthe interior of the first piston and the nozzle, said tube comprising apart of reduced diameter which defines a seat forming one portion ofsaid valve means, the other portion of said valve means comprising a rodconnected to the second piston slidably mounted on said tube and the endof which co-operates with said seat.
 7. An atomizer according to claim2, wherein the second cylinder has opposite the second piston adischarge orifice aligned with an orifice formed in the first piston andcommunicating with the receptacle containing the liquid to be atomized.